• 제목/요약/키워드: Group technology

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위치 정보를 이용한 확장 벡터 모델의 문서 길의 정규화에 관한 연구 (A Study on the Document Length Normalization of Extended Vector Model Using the Information of Location)

  • 김광영;서정현;이민호;주원균;정창후;류범종
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2003년도 춘계학술발표논문집 (하)
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    • pp.1623-1626
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    • 2003
  • 인터넷의 발달과 인터넷 이용자수의 급격한 증가로 정보 검색 시스템의 필요성이 커지고 있다. 또한 대용량의 문서에서 사용자가 원하는 정보를 정확하게 찾기가 점점 어려워지고 있다. 현재 대부분의 검색 시스템들은 문서 길이에 대한 정규화를 처리하고 있다. 현재 문서 길이 정보도 검색 시스템의 검색성능에 기여를 하고 있다. 일반적으로 TREC이나 HANTEC2.0을 이용한 검색 성능 평가를 했을 때문서 길의 정규화를 하지 않는 것보다 한 것이 우수한 성능을 보여 주고 있다. 본 논문에서는 KISTAL2000을 이용하여 위치 정보를 사용하여 문서 길의 정규화 방법에 제시하고 이에 대한 실험하였다.

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투광형 실리콘 슁글드 태양광 모듈을 위한 타공형 스트링 제작 (Fabrication of Perforated Strings for Transparent Silicon Shingled Photovoltaic Modules)

  • 김한준;박민준;송진호;정태웅;문대한;정채환
    • Current Photovoltaic Research
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    • 제8권4호
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    • pp.120-123
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    • 2020
  • Transparent photovoltaics (PV) are used in various applications such as building-integrated photovoltaics (BIPV). However, crystalline silicon (c-Si) is not used for developing transparent PV due to its opaque nature. Here. we fabficate the three holes in 6-inch c-Si solar cells using laser scribing process with an opening area ratio of about 6.8% for transparent c-Si solar modules. Moreover, we make the shingled strings using the perforated cells. Our 7 interconnected shingled string PV cells with 21 holes show a solar to power conversion of 5.721 W. In next work, we will fabricate a transparent c-Si PV module with perforated strings.

Production of Gericudranins by Hairy Root Culture of Cudrania tricuspidata

  • Seo, Weon-Taek;Lee, In-Kyoung;Yoo, Ick-Dong;Park , Young-Hoon
    • Journal of Microbiology and Biotechnology
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    • 제5권4호
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    • pp.234-237
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    • 1995
  • Production of new flavanol derivatives with cytotoxic activity, gericudranin A and B, was studied by using hairy root cultures of Cudrania tricuspidata. Schenk and Hildebrandt (SH) medium was chosen for root growth and gericudranin production. After 35 days culture in a half-strength liquid SH medium containing $30g^{glucose}$/l, hairy root growth reached $138g^{FW}$/I and gericudranin A and B were produced at concentrations of 27mg/l and 21 mg/l, respectively. It was also observed that the contents of gericudranin A and B in hairy root were eight and six times higher than those of cudraniae radix, respectively.

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Quality Evaluation of Pork with Various Freezing and Thawing Methods

  • Ku, Su Kyung;Jeong, Ji Yun;Park, Jong Dae;Jeon, Ki Hong;Kim, Eun Mi;Kim, Young Boong
    • 한국축산식품학회지
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    • 제34권5호
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    • pp.597-603
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    • 2014
  • In this study, the physicochemical and sensory quality characteristics due to the influence of various thawing methods on electro-magnetic and air blast frozen pork were examined. The packaged pork samples, which were frozen by air blast freezing at $-45^{\circ}C$ or electro-magnetic freezing at $-55^{\circ}C$, were thawed using 4 different methods: refrigeration ($4{\pm}1^{\circ}C$), room temperature (RT, $25^{\circ}C$), cold water ($15^{\circ}C$), and microwave (2450 MHz). Analyses were carried out to determine the drip and cooking loss, water holding capacity (WHC), moisture content and sensory evaluation. Frozen pork thawed in a microwave indicated relatively less thawing loss (0.63-1.24%) than the other thawing methods (0.68-1.38%). The cooking loss after electro-magnetic freezing indicated 37.4% by microwave thawing, compared with 32.9% by refrigeration, 36.5% by RT, and 37.2% by cold water in ham. The thawing of samples frozen by electro-magnetic freezing showed no significant differences between the methods used, while the moisture content was higher in belly thawed by microwave (62.0%) after electro-magnetic freezing than refrigeration (54.8%), RT (61.3%), and cold water (61.1%). The highest overall acceptability was shown for microwave thawing after electro-magnetic freezing but there were no significant differences compared to that of the other samples.

천공 효율 향상을 위한 드릴비트 버튼배열 성능평가 방법 (Evaluation of a Drill Bit Button Arrangement for Enhanced Drilling Efficiency)

  • 강훈;조정우;정명식;조용재;이상곤;이재욱
    • 대한기계학회논문집A
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    • 제39권6호
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    • pp.575-581
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    • 2015
  • 드릴비트는 암반에 직접적으로 타격력과 회전력을 전달함으로써 연속적으로 암반을 파쇄, 분쇄하는 천공기의 핵심 구성요소이다. 일정한 속도로 회전하는 동시에 회전축 방향으로 타격하며 암반을 파쇄하기 때문에 암반 파쇄효율을 높이기 위해서는 드릴비트의 배열 최적설계가 필요하다. 그러므로 본 연구에서는 버튼배열 최적화를 수행하기 위한 선행연구로써 버튼배열의 성능을 정량적으로 평가할 수 있는 방법에 대한 연구를 수행하였다. 버튼의 중복타격 면적, 비 타격 면적, 천공편향 모멘트와 같은 평가지표를 활용하여 버튼배열의 파쇄 효율성을 평가하였으며, 더불어 제안된 평가방법을 활용하여 기존 드릴비트 버튼배열의 파쇄 효율성을 검토함으로써 제안한 배열성능 평가방법의 적합성을 확인하였다.

See-through 형태의 투광형 태양광 모듈 제조를 위한 직렬접합형 스트랩 제조 기술 (Fabrication of Series Connected c-Si Solar Strap Cells for the See-through Type Photovoltaic Modules)

  • 박민준;윤성민;김민섭;이은비;전기석;정채환
    • Current Photovoltaic Research
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    • 제11권4호
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    • pp.114-117
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    • 2023
  • Transparent Photovoltaic (PV) modules have recently been in the spotlight because they can be applied to buildings and vehicles. However, crystalline silicon (c-Si) solar modules, which account for about 90% of the PV module market, have the disadvantage of applying transparent PV modules due to their unique opacity. Recently, a see-through type PV module using a crystalline silicon solar strap has been developed. However, there is a problem due to a decrease in aesthetics due to the metal ribbon in the center of the see-through type PV module and difficulty bonding the metal ribbon due to the low voltage output of the strap. In this study, to solve this problem, we developed a fabrication process of series connected c-Si solar strap cells using the c-Si solar cells. We succeeded in fabricating a series connected strap with a width of 2-10 mm, and we plan to manufacture an aesthetic see-through type c-Si PV module.

어깨 안정화운동과 맥켄지 신장운동이 전방머리자세에 미치는 영향 (Effect of Forward Head Posture on Scapula Stability Exercise and McKenzie Stretch Exercise)

  • 박승욱;백용현;서지수;이지현;임상현;이주은;배원식
    • 대한통합의학회지
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    • 제3권4호
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    • pp.61-67
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    • 2015
  • Purpose : The purpose of this study was to find out the effect of exercise on the angle and distance between scapular stability and McKenzie stretch exercise. Method : 30 volunteers took part in this experiment and we divided into three groups(experimental group A, experimental group B, control group C). Experimental group A performed scapular stabilization exercise and experimental group B performed McKenzie neck stretching exercise and control group didn't perform any exercise. Experimental group(A, B) received a total of 12 exercise session over a 4 week period (three times per week). Posture and craniovertebral angle changes of the neck using GPS measurements reported. Result : The CVA and distance change after exercise were significantly reduced in the experimental group A and B. Conclusion : Therefore, we have confirmed through experiments reducing a CVA and distance between scapular stabilization and McKenzie neck stretching exercises, whereby we would also be helpful to ensure the treatment of forward head posture.

The effect of boiled feed on trace elements of longissimus dorsi muscle in Hanwoo steers

  • Kim, Jaeyoung;Jung, Meyungok;Jin, Sangkeun;Seo, Hyunseok;Ha, Jungheun;Choi, Jungseok
    • Journal of Animal Science and Technology
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    • 제63권1호
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    • pp.160-169
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    • 2021
  • Boiled feed is obtained by mixing and boiling agricultural by-products such as rice straw, rice bran, and bean curd with grains. The study explored the change in fatty acid, free amino acid, nucleotide, mineral, cholesterol, myoglobin and collagen of longissimus dorsi muscle in Hanwoo steers fed with boiled feed. Forty steers, 20 heads per group, were divided into two groups: a control group and a boiled feed group. The steers were raised for 10 months. The boiled feed group was enriched with palmitoleic acid, oleic acid, arachidonic acid and unsaturated fatty acids compared with the control group. There were no significant differences in amino acid and nucleic acid composition between the two groups. The boiled feed group contained higher levels of iron and manganese in the boiled feed group compared with the control group. The total cholesterol level was significantly increased, whereas calorie levels, myoglobin and collagen composition showed no differences. As the supply of boiled feed increases the content of fatty acids, unsaturated fatty acids and minerals related to flavor, it should be a feed that leads to the production of high-quality beef.

The Hydroxyl Group-Solvent and Carbonyl Group-Solvent Specific Interactions for Some Selected Solutes Including Positional Isomers in Acetonitrile/Water Mixed Solvents Monitored by HPLC

  • Cheong, Won-Jo;Keum, Young-Ik;Ko, Joung-Ho
    • Bulletin of the Korean Chemical Society
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    • 제23권1호
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    • pp.65-70
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    • 2002
  • We have evaluated the specific hydroxyl group-solvent and carbonyl group-solvent interactions by using an Alltima C18 stationary phase and by measuring the retention data of carefully selected solutes in 60/40, 70/30, and 80/20(v/v%) acetonitrile/water eluents at 25, 30, 35, 40, 45, and 50 oC. The selected solutes are phenol, acetophenone, alkylbenznes(benzene to hexylbenznene), 4 positional isomers of phenylbutanol, 5-phenyl-1-pentanol, 3 positional isomers of alkylarylketone derived from butylbenzene, and 1-phenyl-2-hexanone. The magnitudes of hydroxyl group-acetonitrile/water specific interaction enthalpies are larger than those of carbonyl group-acetonitrile/water specific interaction enthalpies in general while the magnitudes of carbonyl group-methanol/water specific interaction enthalpies are larger than those of hydroxyl group-methanol/water specific interactions. We observed clear discrepancies in functional group-solvent specific interaction among positional isomers. The variation trends of solute transfer enthalpies and entropies with mobile phase composition in the acetonitrile/water system are much different from those in the methanol/water system. The well-known pocket formation of acetonitrile in aqueous acetonitrile mixtures has proven to be useful to explain such phenomena.